Mac OS X only: Free, open source program Monolingual removes the unneeded language files from your Mac in order to save you some precious disk space.

Your mileage may vary in terms of space saved, but in general you can expect to free up anywhere from 100MB to a couple gigs worth of space, depending on the language files that shipped with your computer. These days, 2GB isn't really all that big of a deal, but if you're a stickler for space, Monolingual will definitely help you make a little. We've mentioned it in passing once before, so if you've used Monolingual, let us know how it worked for you in the comments or at tips at lifehacker.com. Monolingual is Mac only. Thanks Steven!